1 Descriptives

1.1 Sociodemographics

Sociodemographic variables reported in the current project include age, gender, and race/ethnicity. Below are descriptions of the US sample (Total N = 7259). The majority of the US sample (84.17%) are Non-Hispanic White with minority groups represented at lower rates (Race: 2.44% Black; 2.56% Asian/Pacific Islander; 5.10% Other/Mixed Race; Ethnicity: 8.14% Hispanic/Latino).

At the time of assessment, the average age of participants was 33.66 (SD = 12.61). All participants (n = 7259) reported their age

With regards to sex and gender, the majority of the sample (88.61%) identified as women, with 6.46% identifying as nonbinary and 4.50% identifying as men. 96.25% of the sample were assigned female at birth.

1.2 Eating Disorder Diagnosis Groups

The ED100K-v3 (Thornton et al., 2018a): self-report diagnostic questionnaire for eating disorders that is based on the Structured Clinical Interview for DSM-5 (SCID). The ED100K-v2 yields DSM-5 lifetime diagnoses of AN, BN, and BED. The ED100K has previously been validated against the SCID (Thornton et al., 2018b).

In terms of eating disorder diagnostic groupings, 64.09% of participants reported a history of symptoms consistent with a diagnosis of AN, 47.05% of participants reported a history of symptoms consistent with a diagnosis of BN, and 31.86% of participants reported a history of symptoms consistent with a diagnosis of BED. When taken together, 41.64% of the sample reported a history of AN only, 12.37% reported BN only, 9.1% reported BED only, 14.12% reported AN and BN, 14.44% reported BN and BED, 2.20% reported AN and BED, and 6.12% reported all three disorders. For analyses, individuals with single diagnoses are considered as independent groups. Groups with mixed diagnoses were categorized as a ‘mixed, restrictive spectrum’ (AN + BN, AN + BED, AN + BN + BED; 22.44%) or ‘mixed, binge spectrum’ (BN + BED; 14.44%)

1.3 Weight History

There were 25 individuals who reported a current BMI > 70 or < 10 and 77 individuals who reported weight suppression values that were high (> 250 lb difference between highest weight and current weight or current weight and lowest weight, or negative weight suppression values – i.e. a current weight that is higher than one’s highest ever weight, or a lowest weight that is higher than one’s current weight)

BMIs of > 70 and < 10 were removed for data integrity. Weight history is presented in table 1.1. Note - there are some out of range values for weight suppression we have to decide what we want to do with these

Table 1.1: Weight History
vars n mean sd median trimmed mad min max range skew kurtosis se
Height 1 7259 65.14 3.04 65.00 65.06 2.97 53.00 82.00 29.00 0.43 1.39 0.04
Current Weight 2 7259 160.50 68.34 140.00 151.51 37.06 0.00 3000.00 3000.00 11.32 417.01 0.80
Lowest Weight 3 7259 115.46 36.13 107.00 110.28 25.20 45.00 480.00 435.00 1.92 6.00 0.42
Highest Weight 4 7259 186.42 78.30 165.00 175.62 48.93 0.00 3000.00 3000.00 8.68 252.71 0.92
Current BMI 5 7259 26.54 11.36 23.40 25.08 5.99 0.00 548.65 548.65 14.88 623.71 0.13
Highest BMI 6 7259 30.83 13.02 27.25 29.11 7.58 0.00 548.65 548.65 11.66 389.35 0.15
Lowest Adult BMI 7 7259 19.08 5.59 17.63 18.28 3.56 5.63 72.33 66.70 1.98 6.70 0.07
Current Weight Suppression 8 7259 25.92 35.48 17.00 20.29 17.79 -290.00 1543.00 1833.00 12.51 468.18 0.42
Current vs.Lowest Weight 9 7259 45.04 52.93 34.00 38.83 28.17 -128.00 2905.00 3033.00 23.54 1192.57 0.62

1.4 Eating Disorder Variables

Eating disorder variables was assessed by three varying assessments - the ED100k; EDEQ, and CET.

1.4.1 ED100k

For current paper – we use an item from the ED100k that captures historical exercise for weight and shape control. This question asked if exercise was ever used as a behavior to intentionally control weight or shape, with options of Never (n = 945; 13.02%), A few times, but never became a habit (n = 1710; 23.56%), and More often (n = 4604; 63.42%).

1.4.2 EDEQ

The Eating Disorder Examination-Questionnaire (EDE-Q v 6.0) (Fairburn, 2008; Fairburn & Beglin, 1994) is a valid, reliable self-report questionnaire of cognitive and behavioral symptoms of eating disorders over the prior four weeks. The questionnaire has four subscales (Restraint, Eating Concern, Shape Concern, Weight Concern), a Global scale, and items that measure fasting (item 2), objective binge eating (item 15), self-induced vomiting (item 16), laxative use (item 17), and driven exercise (item 18), “Over the past 28 days, how many times have you exercised in a driven or compulsive way as a means of controlling your weight, shape, or amount of fat, or to burn off calories)”. 6290 individuals completed at least 75% of EDEQ global items. Descriptive information for EDEQ subscales is presented in table 1.2

Table 1.2: EDEQ Subscales
n mean sd median trimmed min max range skew kurtosis se
Restraint 6287 2.85 1.90 3.00 2.82 0 6 6 0.02 -1.26 0.02
Weight Concern 6105 2.84 1.90 3.00 2.81 0 6 6 0.02 -1.26 0.02
Eating Concern 6132 2.67 1.68 2.80 2.65 0 6 6 0.04 -1.10 0.02
Shape Concern 6104 4.17 1.65 4.62 4.36 0 6 6 -0.82 -0.40 0.02
Global 6290 3.13 1.62 3.28 3.18 0 6 6 -0.20 -1.05 0.02

With regards to eating disorder behaviors at present, individuals reported a range of ongoing ED behviors (see table 1.3). Note – need to decide what to do with out of range values While about half (46.92%) of individuals reported any driven exercise in the past four weeks, a smaller number (13.38%) reported driven exercise more than 20 times in the past 28 days.

Table 1.3: EDEQ Behaviors
n mean sd median trimmed min max range skew kurtosis se
Laxative Use 6136 1.57 5.66 0 0.16 0 150 150 7.26 107.71 0.07
Vomitting 6144 3.06 12.33 0 0.49 0 400 400 11.90 254.49 0.16
Driven Exercise 6149 5.64 8.95 0 3.72 0 85 85 1.85 4.15 0.11
Binge Eating (days) 5701 4.23 7.43 0 2.44 0 120 120 2.55 13.48 0.10
Fasting (Oridnal 0-6) 6280 1.73 2.06 1 1.41 0 6 6 0.95 -0.50 0.03

1.4.3 CET

The Compulsive Exercise Test (CET) (Taranis et al., 2011): In response to the limitations of previous measures of compulsive exercise, Taranis et al. (2011) developed the CET. The CET is designed to facilitate tests of an empirically supported cognitive behavioral model of compulsive exercise within the context of eating disorders. The CET represented a shift in the focus of measures of compulsive exercise, as it was designed to capture the features of compulsive exercise most relevant for understanding eating disorders, rather than earlier simplistic measures which focused on quantity of exercise and did not capture psychological dependence. The CET is based on four key factors proposed to characterise compulsive exercise based on Meyer, Taranis, Goodwin, and Haycraft (2011) cognitive-behavioural model: eating psychopathology, obsessive compulsiveness, affect regulation, and perfectionism. In this model, compulsive exercise differs from healthy exercise in that compulsively exercising individuals present with weight and shape concerns, persistently continue exercising with the aim to avoid guilt or negative affect, and have very rigid, ritualistic and inflexible attitudes towards their exercising behaviour (Meyer et al., 2011). The time frame measured is current and the CET has a total score and five subscales. There is also a clinical cutoff defined for the scale, which can be used to define CE presence vs. absence.

Only a subset (n = 4640) of participants completed the CET

Subscale and total score information for the CET is presented in Table 1.4. Of those completing the CET, about a third (34.38%), met clinical cutoff for current compulsive exercise.

Table 1.4: CET Subscales
n mean sd median trimmed min max range skew kurtosis se
Avoidance and Rule-Driven Behavior 4608 2.08 1.47 1.88 2.01 0.00 5 5.00 0.34 -0.92 0.02
Weight Control 4630 3.10 1.30 3.20 3.17 0.00 5 5.00 -0.39 -0.72 0.02
Rigidity 4579 2.49 1.47 2.67 2.50 0.00 5 5.00 -0.08 -1.02 0.02
Mood Improvement 4627 3.13 1.30 3.20 3.21 0.00 5 5.00 -0.50 -0.42 0.02
Lack of Enjoyment 4584 2.40 1.41 2.33 2.35 0.00 5 5.00 0.31 -0.89 0.02
Total 4640 13.20 4.17 13.09 13.21 1.67 25 23.33 0.02 -0.59 0.06

2 Maladaptive Exercise across Diagnosis, Age, Gender, and Weight History

Considering across diagnosis, the following describes rates of (1) maladaptive exercise history; (2) rates of CET clinical cutoff being met, and (3) current CET symptom scores

2.1 Diagnosis Groups

2.1.1 CET Clinical Cutoff

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2.2 Age

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2.3 Gender

2.4 Weight History

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